package three;

public class jiecheng {
	public static void main(String[] args) {
		int s =cj(1);//1.2.3.4.5????
		System.out.println(s);
	}

	 static int cj(int i) {
		if (i==1||i==0) {
			return 1;
		} else {
			int sum = 0;
			sum = i * cj(i-1);
			return sum;
		}
		}

}